window.onscroll = function () {
    const scrollTop = document.documentElement.scrollTop || document.body.scrollTop

    console.log(scrollTop);
    if (scrollTop > 888) {
        // 让回到顶部元素显示出来; 
        // console.log("回到顶部元素显示")
        document.querySelector(".back-top").style.display = "block";
    } else {
        // 让回到顶部元素隐藏起来; 
        // console.log("回到顶部元素隐藏")
        document.querySelector(".back-top").style.display = "none";
    }
}
document.querySelector(".e-back-top").onclick = function () {
    scrollTo({
        top: 0,
        behavior: 'smooth'
    });

}